package com.itheima.service.UserServiceImpl;



import com.itheima.mapper.UserMapper;
import com.itheima.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserServiceImpl {

    @Autowired(required=false)
    private UserMapper userMapper;

    public User queryById(String username) {
        //int i=1/0;
        return userMapper.findById(username);
    }
}